Point is India has other options including the F-35. While, Russia can't afford another Stealth Fighter. Nor, does it have the time to develop one. Even if it had the resources to do so. (which it doesn't)

Nonetheless, if you have a viable alternative I am all ears.....

Simple actually, they will keep buying Mig-35s (whatever the next variant of that is) and Su-35's and Su-30SMs and Su-57's. They will buy these then tell all there people they can decimate anything through some magical tech or tactic that only they can do. Why? Because they are Russia, you forgot how proud the Russians are, they will never give up the bulk of there fighter force production to China.

Sorry, Russia gave away the bulk of their export fighter market. When they decided to develop the PAK-FA (Su-57) over the LMFS!

They'll continue to refine the SU-57, much like the Flanker series. In fact, I consider the SU-57 the ultimate evolution of the Flanker series. Same podded engines, tunnel/weapons bay, tail stinger etc.. It looks like someone stepped on a Flanker..

But acquisition numbers will be low. A LOT lower than the SU-27 and its subsequent iterations. If I've learned anything by watching the F-22/F-35 developmental cycle, it's this: Building, flying and perfecting a 5th generation bird is extremely difficult. We're hearing about 2nd stage engines now for SU-57, but what about the avionics?

Those seemed to be the most difficult hurdle to overcome, at least on the F-35. It may be they develop a LO design, with great range/speed/maneuverability.... but it'll be hamstrung by its avionics suite.

mixelflick wrote:They'll continue to refine the SU-57, much like the Flanker series. In fact, I consider the SU-57 the ultimate evolution of the Flanker series. Same podded engines, tunnel/weapons bay, tail stinger etc.. It looks like someone stepped on a Flanker..

But acquisition numbers will be low. A LOT lower than the SU-27 and its subsequent iterations. If I've learned anything by watching the F-22/F-35 developmental cycle, it's this: Building, flying and perfecting a 5th generation bird is extremely difficult. We're hearing about 2nd stage engines now for SU-57, but what about the avionics?

Those seemed to be the most difficult hurdle to overcome, at least on the F-35. It may be they develop a LO design, with great range/speed/maneuverability.... but it'll be hamstrung by its avionics suite.

Hell, do they even have an AESA radar flying yet?

I think the similarities are largely superficial, or they are things that are quite common in modern fighter aircraft. The F-16 has a podded air intake, a subtly blended fuselage and wing, and moderate sweep wings combined with a vortex-generating strake. Would you describe the Flanker as a twin-engine F-16? The F-14 has wide-set engines fed by podded air intakes, a pancake fuselage, weapons storage in between the air intakes, and even a (modest) tail stinger. Would you describe the SU-27 as a fixed-wing Tomcat?

I think that most of the development of cutting-edge Russian systems is going on in secret. The pictures of the T-50 prototypes that are released to the public are carefully censored. Note that in however many years it's been since the first prototype flew, there are still no public photos of the weapons bays. Piotr Butowski states that the next-gen Russian SRAAMs were test-fired about a year ago, and yet no pictures of those have been forthcoming.

So what you see with the T-50/SU-57 prototypes in pictures isn't the whole story.

Something similar is going on with the T-14 tank. The same prototypes are brought out for parades every Victory Day, but a lot of the systems on them are clearly placeholders. The actual development of that tank is going on somewhere else, out of sight.

Corsair1963 wrote:Honestly, I don't see the Su-57 coming in under $100 Million. Which, should put the J-31 is an excellent position to win some export orders for China.

The Chinese birds certainly look a lot stealthier, but that hardly spells game over for the export of Russian fighters, the way you've been implying in poorly-written missives punctuated with smilies for the past week or so.

A fifth-generation fighter is more than just its frontal RCS. There are several reasons why a prospective buyer might potentially opt for the SU-57 over the FC-31 that your simplistic analysis has completely ignored.

Every fighter aircraft ever made has lived or died by its engines. A fighter's engines need to be powerful relative to their weight, flexible, responsive, and as reliable as possible. Of course, all of these requirements contradict each other at some level. A higher bypass ratio will improve static SFC, but at the expense of responsiveness, for example.

Russia has established gas turbine design houses, China does not. China is spending a lot of money in order to be able to to design and build their own engines, but the initial results were not impressive and they're probably not there yet. Note that their C-17 looking transport aircraft is still using turbojets, or possibly low bypass turbofans. It is supposed to receive high bypass engines at some point in the future, but the fact that they aren't ready now does not say flattering things about the maturity of Chinese aero turbines. The pilots' comments on the WS-10 engines used occasionally in substitution for AL-31s in their J-10s and Flanker clones are not encouraging either.

So, at this very moment, the Russian engine designers are probably still miles ahead of the Chinese ones, even if the Chinese are putting a lot of money and effort into closing that gap.

There's also the question of avionics. Everyone and their dog knows that the Russians are far behind the US in this regard, but how do the Russians and Chinese compare? A superficial analysis would suggest the Chinese are ahead because they have a larger domestic electronics manufacturing sector. But military avionics aren't really the same as consumer electronics, and it's not obvious that expertise in manufacturing consumer electronics translates to expertise in the design and manufacture of military electronics. When you consider that most of the electronics made in China are designed elsewhere, then the situation isn't such an obvious slam-dunk advantage for the Chinese side anymore.

The fact that China just bought two dozen or so SU-35 Flanker-Es suggests that they still have quite a bit to learn from the Russians in this area.

On top of that, some countries are simply too politically hostile to China to ever countenance buying weapons from them. India and Vietnam are at the top of that list. Vietnamese politicians aren't going to say "hey, I know that China is considered our primary strategic threat, and that our country actually went to war with them between 1979 and 1990, but I think we should let bygones be bygones because I have been looking at pictures on the internet and the FC-31 totally has better management of specular X-band returns than the SU-57." Likewise, the idea that Indian politicians will one day wake up and say "Wow, I just realized that our decades long policy of buying combat aircraft from both the USSR/Russia and the West to ensure India's armed forces cannot be strangled by changes in international politics is obsolete. We should totally cede our claims to the Arunachal-Pradesh because then maybe China would give us J-20s. What are territorial claims compared to slightly superior planform alignment?"

With moderate investment, Russians are going to easily outdo the Chinese in engine tech for the foreseeable future.As for all the talk about "Chinese" semiconductor industry- that's mostly capable only of making copies based on somewhat obsolete tech. And if you're buying proper power electronics, forget about the Chinese (PRC). ROC, on the other hand, is a different story.Su-57 has potential on the markets of countries that won't be able to get F-35, and I wouldn't dare to bet on the prospective "J-31" since not much is known about it, or even what it promises. (from what I've read, J-20 is unlikely to be exported).A lot of us here like to rib on the Su-Pancake due to being fed up by all the "F-35 killer" hype around this latest wunderwaffe, but honestly, the plane could be worse, and is a fair effort for a country as cash-strapped as Russia.

juretrn wrote:With moderate investment, Russians are going to easily outdo the Chinese in engine tech for the foreseeable future.As for all the talk about "Chinese" semiconductor industry- that's mostly capable only of making copies based on somewhat obsolete tech. And if you're buying proper power electronics, forget about the Chinese (PRC). ROC, on the other hand, is a different story.Su-57 has potential on the markets of countries that won't be able to get F-35, and I wouldn't dare to bet on the prospective "J-31" since not much is known about it, or even what it promises. (from what I've read, J-20 is unlikely to be exported).A lot of us here like to rib on the Su-Pancake due to being fed up by all the "F-35 killer" hype around this latest wunderwaffe, but honestly, the plane could be worse, and is a fair effort for a country as cash-strapped as Russia.

I agree that for a "moderate investment" the Russians could stay ahead of the Chinese in fighter engine tech, but can they afford a moderate investment? That's the big question. Russia has about the same GDP as Spain.

I think your assessment is accurate in general. All I would add is that it isn't just that the Russians have had less money to spend on R&D, they also had the entire period of the 1990s where their R&D came to a standstill, and a lot of scientists left the country. The US has more resources, and they need to play catch-up there, but they also need to re-build infrastructure that was neglected for over a decade.

The fact that they can make a fifth-generation fighter at all is impressive.

WIth respect to the design largely being superficial, I'm not so sure.

The twin intakes, cavernous "tunnel" for weapons and other design features of the SU-57 represent a comfort zone of sorts. It worked for them on the Mig-29, SU-27/35 and they're sticking with it. If it's such an efficient/effective design though, why hasn't Lockheed Martin followed suite? It's 2 5th gen birds have plenty of body/blended wing lift plus chines - but no widely spaced nacelles, engines etc.

It just seems that after the F-14, we got away from that arrangement and I'm guessing with good reason. Look at the F-15.. tremendous lift to the point it landed once on one wing! I dunno.. It just seems like the SU-57 is more an evolution of the Flanker than anything else. I could be wrong, and I guess time will tell...

mixelflick wrote:WIth respect to the design largely being superficial, I'm not so sure.

The twin intakes, cavernous "tunnel" for weapons and other design features of the SU-57 represent a comfort zone of sorts. It worked for them on the Mig-29, SU-27/35 and they're sticking with it. If it's such an efficient/effective design though, why hasn't Lockheed Martin followed suite? It's 2 5th gen birds have plenty of body/blended wing lift plus chines - but no widely spaced nacelles, engines etc.

It just seems that after the F-14, we got away from that arrangement and I'm guessing with good reason. Look at the F-15.. tremendous lift to the point it landed once on one wing! I dunno.. It just seems like the SU-57 is more an evolution of the Flanker than anything else. I could be wrong, and I guess time will tell...

Widely spaced engines make a great deal of sense on a fifth generation fighter, and there's no reason to think that they're a holdover from older aerodynamic studies.

A fifth generation fighter needs to have internal weapons. Until some enterprising design team puts the air intake on the top of the fighter, this means that there is a potential for the airflow to be disturbed by the weapons bay doors opening. If you have read about the operational history of the F-14A, you know that it can be very, very bad if the engines eat disturbed airflow.

Placing the air intakes far apart, but on the bottom of the fuselage gives good pressure recovery at high AOA while minimizing the likelihood of problematic weapon bay door/intake interactions. It's a sensible enough design for a fifth gen that Northrop opted for something very similar with the YF-23.

The semi-podded configuration has a number of other advantages. As I said before, the design is amenable to enlarging the intakes. The tunnel usually offers some sort of flow straightening benefit too, which can help economize on vertical fin size. Widely spaced engines usually offer a small reduction in base drag and a small boost in thrust because the engine flows don't interfere with each other.

On the flip side, the F-22/F-35 style air intakes have much less wetted area and probably a more favorable surface area to volume ratio. The intakes are also longer, which may give them an advantage in stealth or pressure recovery over certain portions of the flight envelope. The Lockheed design probably has a lower RCS from the side as well.

The point here is that there are so many different factors to consider that saying on design is "more efficient" than another is meaningless. Everything in aircraft design is a trade-off of hundreds of different parameters. You can, at best, look at combined performance metrics (like E-M plots) and flight manuals to understand where the designers were trying to make the aircraft excel, and what they were willing to let slide.

I don't see any reason to think that the engine configuration of the SU-57 is a holdover from the SU-27. If the widely spaced engines and intakes were a holdover, then why does the SU-47 have closely spaced engines like an F-15 with quarter-circle-shaped pitot air intakes?

I'm also dubious that old wind tunnel data could be re-used in any meaningful fashion. Both the SU-27 and SU-57 place the air intakes underneath the LERX/wing root. This area also acts as a vortex generator for the main wing. Vortex/wing interactions are an important part of fourth and fifth generation fighter design, but they're tricky to get right and require hundreds to thousands of computer and wind tunnel iterations to perfect. The SU-57 wing and wing root are not copypasted from the SU-27; the LERX is larger and has variable geometry while the main wing is much more swept.

I suppose there could have been some hairy-eared engineer who had been around for the T-10 program who insisted on the semi-podded configuration and denounced the SU-47 design as a foolish side distraction, but realistically going back to the semi-podded engine installation would not have saved any time. The CFD and wind tunnel testing would all need to be done anew. At that point, it's speculation on the mindset of the engineers and not on the actual aerodynamics of the aircraft.

Last edited by collimatrix on 18 May 2018, 03:35, edited 1 time in total.

I think when looking at Russian and Chinese aircraft industry development it's helpful to keep in mind that where it's most difficult for them to catch up is not design but manufacturing and integration.

By now everybody knows how to do basic stealth shaping. With great examples like the F35 flying around, powerful computational packages and petaflop supercomputers how hard can it be for smart people to come up with good shapes?

The real problem is, signature reduction needs to happen by dB, ie, on a log scale. You're always chasing down finer and finer details. You got the shape right? Great! That got you 5 dB, but now you have to make perfect creases and edges.

Sooner or later along this process, you hit a brick wall defined by your materials technology and manufacturing precision. Your progress comes to a dead stop because you can't manufacture, then you can't test, you can't verify, you can't refine.

From the manufacturing quality on those su-57s, I'd guess they hit their brick wall some where near the Super Hornet's signature level. All the rest are just for show.

Same applies even more to engines. Want to do 5th gen engines? Better learn to do those ceramic matrix composites.

Same with radar.

Difference between China and Russia is:

Huge capabilities now in high precision manufacturing.Monster effort at advanced materials R&D.

China has overtaken the US as the largest publisher of high quality, high impact academic research in materials science. They are the new world leaders in fundamental academic research in this area. Granted it's different in industry, but that shows you the depth of commitment and the potential.

My prediction is that China will eclipse Russia in all areas of military aviation in the next 5 to 10 years. Air frames, engines, avionics, everything.

citanon wrote:I think when looking at Russian and Chinese aircraft industry development it's helpful to keep in mind that where it's most difficult for them to catch up is not design but manufacturing and integration.

By now everybody knows how to do basic stealth shaping. With great examples like the F35 flying around, powerful computational packages and petaflop supercomputers how hard can it be for smart people to come up with good shapes?

The real problem is, signature reduction needs to happen by dB, ie, on a log scale. You're always chasing down finer and finer details. You got the shape right? Great! That got you 5 dB, but now you have to make perfect creases and edges.

Sooner or later along this process, you hit a brick wall defined by your materials technology and manufacturing precision. Your progress comes to a dead stop because you can't manufacture, then you can't test, you can't verify, you can't refine.

From the manufacturing quality on those su-57s, I'd guess they hit their brick wall some where near the Super Hornet's signature level. All the rest are just for show.

Same applies even more to engines. Want to do 5th gen engines? Better learn to do those ceramic matrix composites.

Same with radar.

Difference between China and Russia is:

Huge capabilities now in high precision manufacturing.Monster effort at advanced materials R&D.

China has overtaken the US as the largest publisher of high quality, high impact academic research in materials science. They are the new world leaders in fundamental academic research in this area. Granted it's different in industry, but that shows you the depth of commitment and the potential.

My prediction is that China will eclipse Russia in all areas of military aviation in the next 5 to 10 years. Air frames, engines, avionics, everything.

Russian industry has become a paper tiger. China is a true dragon.

Wow. 5 to 10 year? That fast??

I suppose its not out of the realm of possibility just looking at the SU-57/J-20 situation. The Russians seem dead in the water or close to it, while the Chinese are fielding operational aircraft/squadrons. Of course nobody knows just how stealthy/5th gen the J-20 is. It might be it's not, and they're rushing it into service just to say otherwise. That's going to show up real fast in operational deployments though, and certainly in the export market if the J-31 falls far short of the F-35's benchmark...

I suppose its not out of the realm of possibility just looking at the SU-57/J-20 situation. The Russians seem dead in the water or close to it, while the Chinese are fielding operational aircraft/squadrons. Of course nobody knows just how stealthy/5th gen the J-20 is. It might be it's not, and they're rushing it into service just to say otherwise. That's going to show up real fast in operational deployments though, and certainly in the export market if the J-31 falls far short of the F-35's benchmark...

There's "operational" and then there's operational. It took ~22 F-35s to conduct SDD testing, not to mention the upcoming IOT&E testing. We're using over 100 F-35s training pilots and maintainers, in addition to the ~4 operational squadrons. The Chinese have ~20 J-20s total. Let's consider how "operational" they are likely to be, at this point in development.

Apparently spotted by the SU-30MKI's radar. If true, this is really good news for the US. It's hard to say though. Maybe the J-20 wasn't flying in a stealth configuration?

Indians can claim whatever they want, this info is on par with "our fighters got on Raptors' six o'clock" Sputnik reports.

Think about it: India was supposed to have FGFA, the ultimate 5th gen fighter. Better than Raptor, better than Lightning, better than J-20 and even better than Su-57! Made in India too, using superior DRDO tech. Fast-forward ten years to present day: China celebrates first J-20 squadron as operational and combat capable, meanwhile India not only does not have the promised fighter, they didn't get the desired tech transfer from Russians even though they dumped a couple hundred million dollars into the project. Even if they stay with Sukhoi, it seems that J-20 already outpaces Su-57 development. What are Indians' options: put everyone responsible on trial or pump out stonkism news reports that J-20 is actually shite and "does not change the balance of power" cause it's easily defeatable bu Flankers?